Colorado improved to 5-1 on a seven-game trip that started in Washington, and the Rockies are 9-4 on the road overall.

The announced attendance was 8,869, but there appeared to be fewer than 2,000 fans at PNC Park. The Pirates offered ticket vouchers for games later in the season to fans who came through the turnstiles.

“Walking in from the bullpen, I was a little concerned because it was really cold,” Bettis said. “But I put on some [handwarmers] once I got to the dugout and I was fine.”

Trevor Williams (3-1) threw six innings in short sleeves despite the 34-degree temperature at first pitch. He gave up two runs and four hits, and he has allowed five runs in four starts this season.

Williams grew up in San Diego and played at Arizona State. He had never pitched in snow before.

“I’m hoping that this is going to be the last one,” Williams said. “It’s tough waking up and seeing a blizzard outside, but it’s tough for them, too.”

Bettis has pitched at least five innings and given up two runs or fewer in each of his four starts this season. He has a 1.47 ERA in his past six starts, including his final two outings of 2017.

“He lives on the margins,” Pittsburgh manager Clint Hurdle said. “He changes speeds. He’s got a little quick pitch in there that he ran at us a few times, as well.”

Colorado went ahead in the first when Gerardo Parra drew a one-out walk, took third on Charlie Blackmon’s single and scored when Carlos Gonzalez grounded into a forceout. Blackmon has eight RBIs in his last four games.

Rookie Ryan McMahon, who entered hitting .074, singled in a run in the fourth to make it 2-0.